In this paper, the authors develop a probabilistic model in order to analyse the reliability of metallic targets impacted by cylindrical metallic projectiles (resulting from industrial facilities explosion, for instance). The random variables are the projectiles features (mass, velocity at impact, incidence angle between the projectile and the target plane, the diameter) and the target properties (ultimate strength and strain of the constitutive material as well as the target thickness). A simplified mechanical model is proposed. in the case of cylindrical projectiles and planar targets. It relies on the hypothesis of plastic behaviour of the target constitutive material whereas it assumes that the projectile behaves as a rigid body. The theoretical penetration depth into the target is compared with experimental data collected from existing references. A probabilistic error model is associated to the mechanical model. The log-normal and Gamma distributions describe correctly the uncertainties that affect the whole governing parameters (mechanical simplifications, projectile dimensions, velocities and incidence angles at impact, ultimate strength and stress of the target constitutive material, etc.). (C) 2008 Elsevier Ltd. All rights reserved.